EditorSettings.projectGenerationUserExtensions

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public static string[] projectGenerationUserExtensions ;

Description

Controls list of extensions of files that will be included in the c# .csproj projects that Unity generates.

Use this if you have certain file formats that you'd like to add to the .csproj files for convenient editing. This setting takes a semicolon-separated string of extensions. Leading dots are optional. This setting is specific to a project. In addition to these extensions, there is also a hardcoded built-in list of extensions that is always included at EditorSettings.projectGenerationBuiltinExtensions.

using UnityEngine;
using UnityEditor;

public class Example { [MenuItem("TryMe/SetExtensions")] static void Doit() { EditorSettings.projectGenerationUserExtensions = new[] { "txt", "xml", ".cs", "myfunkyformat"}; } }